Roll out your puff pastry on a lightly floured surface. Transfer it to a baking sheet lined with parchment paper.
Arrange the apple slices on the pastry, leaving a 1-2 inch border around the edge.
Sprinkle the sugar evenly over the apples, then dot with butter.
Fold the pastry edges up and over the apples to create a border.
Bake for 45-50 minutes, or until the pastry is golden and the apples are tender.
Let cool before serving.
Notes
Make sure to thinly slice the apples to ensure they cook evenly.
• Leaving a border when placing your apple slices on the pastry helps to avoid leakage and gives a rustic look.
• Brushing the pastry with a beaten egg before baking will provide a beautiful golden color.
• Let the galette cool completely before cutting to allow the filling to set and avoid it being runny.
• You can sprinkle a bit of cornstarch over the apples before baking if you are worried about too much juice releasing and making the pastry soggy.